My Music Theory for Dummies book says in several places that their is supposed to be a "cheat sheet inside the front cover of this book." The only thing on the inside cover is an ad for "get more and do more at dummies.com." It does have a link to www.dummies.com/cheatsheet/musictheory, which does have a cheat sheet for the book, but not the "circle of fifths" referenced in the book.